Rolling mill for the production of metal sheets or plates



liatented Apn i9, i927.

itllli'll STATES P'lENT GFFIQE.

HECTOR LEIGETON DAVIES, OF GOW'ERTON, NEARSWANSEA, ENGLAND, AND SAMUEL.

BEES COUND, OF ABERAVON, 'WALES ROLLING MILL FOB THE PRDUCTON'OF IYIETL SHEETS OR PLATES.

Application lcd October 27, 1.9%, Serial Nm 746,110, and in Great Britain November 2,- 1923.

This invention relates to processes and apparatus whereby metal sheets or plates arey produced by subjecting the metal in successive stages to repeated heating and rolling operations, firstly in its original state in the form of a bar and thereafter, after havingv been folded or doubled on itself and trimmed on emerging from the preceding rolling` operation, in the forni of two, four and usually eight-fold sheets, which constin tute what is know as bones and are nally trimmed, cut to the required lengths and separated.

According to the generally adopted practice, these successive stages are all performed in a single unit of apparatus comprising a furnace, rolling mill and finishing mill together with a folder and trimmer. This method is slow and dilatory and causes great difficulty to the operators and unfavorably affects both output and cost of production.

According to the present invention, while each stage (by which we mean the period -between two successive heatings) is carried out on one rolling mill, separate apparatus viz, furnace, rolling mills, doublers and trimmers are provided` for each. stageand these are so arranged that the work travels forward in continuity in one direction from stage to stage. At least three sets of apparatus for different stages are provided.

It has also been suggested, though we bei lieve it has never been put into practice, at any rate in Great Britain, to provide a large number of rolling mills so that, generally speaking, the work continually passes from one to another both in the same stage and in different stages. The disadvantages of this are that rolls in fact have slightly different contours and work emerging with the contour given by such rolls should, if it is not to be reheated, again be placed in rolls on the same contour, otherwise undesirable strains arise. This is aggravated if one set of rolls is continually occupied with work fresh from the furnace, while the next set is similarly occupied with work which has cooled during one re-rolling, and the next'by still cooler work, since different expansions occur in the rolls owing to the changes of temperature which further affect the contours. Furthermore this arrangement of multiple rolling mills requires eX- cessive floor space which adds to the cost-of production.

Other suggestions have been made bywhich the work is passed-througha plural-r ity of rolling mills in all its stageswithout` reheating, or is re-rolled after doubling`r without reheating; or the sheets are. rolled first and then in pairs without reheafting; but. these differ from the present invention in which rolling, whether singly or in pairs, takes place immediately after the sheets have come from the furnace and before any intermediate operations have been perform-V ed, and rolling singly, in pairs, in fours etc.

are each performed on different rolling mills.A

The present invention avoids these difficulties by subjecting the work at each stage to the action of one set of rolling millsv only, while greatly facilitating out-put byv constructing the apparatusso that each stageis carried out entirely separately and the shaft, but to great difficulty in carrying out` the rolling processes. For these reasons we propose, when more than one unit of apparatus is employed, to arrange such units in pairs, symmetrically in relation to the driving means and in such a manner that the respective rolling mills of the two units performing the same stage in the sequence of operations are placed in axial alignment opposite each ',other. While the "mills performing different stages in each unit can thus be driven each by its separate driving shaft, the arrangement allows the corresponding mills of the twoy units which operate under like working conditions to be coupled in pairs on the same shaft.

Referring to the drawings, which form part of this specification, the 'ligure represents, as an example, a plant with two units arranged according to the present invention.

Each of these units comprises symmetrically arraneed opposite each other a furnace A, a roughing mill B, a doubler and trimmer C, and an intermediate furnace A1, an intermediate rolling mill B1, a doubler and trimmer C, a second intermediate furnace A2, rolling mill B2, and doubler C2, and finally a finishing furnace A3, and a finishing mill B3.

The two roughing mills B, B, the two intermediary mills B1, B1, and the two further'intermediate mills B2, B2, and the two finishing mills B3 are mounted in pairs on parallel shafts, D, D1, D2, and D3 respectively, which shafts are, centrally between the two mills, driven by spur and belt gearing from the engine or motor E.

The raw material in the form of bars, after being heated in the furnace A is passed through the roughing mill B, then doubled and trimmed at C. The twofold sheet is now subjected to the second stage of operations by being rs1-heated at A1, and then sent first through the intermediary mill B1 and then on to the doubler and trimmer C1 where the double sheet is folded into four folds. The third stage now begins, and during this stage it is again re-heated at A2, rolled in the mill B2 and folded into eight folds and trimmed at C2, and the eight fold sheets starting now on their final stage of operations are re-heated at A3, and finally rolled in the mill B3.

By means of this new apparatus it is estimated that boxes can be produced with a very considerable reduction of the labour formerly required, and that the cost of plant for a given output will also be substantially reduced.

We claim:-

l. A rolling mill installation, comprising a prime mover; a pair of furnaces at opposite sides thereof; a plurality of pairs of rolling mills disposed one after another beyond the prime mover, the mills of each pair having a shaft common thereto and whereon they are mounted in symmetrical relation to each other at opposite sides of a median line which intersects all'the shafts centrally; gearing for driving the several shafts from the prime mover; a pair of doublers associated with each pair of mills and disposed symmetrically with relation thereto and at opposite sides of the median line; and a pair of furnaces between each pair of doublers and the succeeding pair of mills and likewise disposed at opposite sides of said line.

2. A rolling mill installation, comprising a prime mover; a plurality of pairs of rolling mills disposed one after another beyond the prime mover, the mills of each pair having a shaft common thereto and whereon they are mounted in symmetrical relation to each other at opposite sides of a median line which intersects all the shafts centrally; gearing for driving the several shafts from the prime mover; and a pair of doublers associated with each pair of mills and disposed symmetrically with relation thereto and at opposite sides of said line.

3. A multistage rolling mill installation for producing multifold metal sheets and plates, comprising two units of apparatus arranged in pairs and including rolling mills, and driving means therefor; the respective rolling mills of the two units performing the same stage in the sequence of operations being placed in axial alignment and coupled in pairs upon common shafts.

In testimony whereof we afiiX our signatures.

HECTOR LEIGHTON DAVIES. SAMUEL BEES COUND. 

